Intraneural ganglion cyst of the tibial nerve

A Rare Case of Tibial Intraneural Ganglion Cyst Arising From the Tibiofibular Joint

Intraneural ganglion cysts are a rare occurrence. They are most commonly found originating from the common peroneal nerve but are also frequently reported on the radial, ulnar, median, sciatic, tibial, and posterior interosseous nerves. A typical clinical presentation is posterior knee and calf pain resulting from tibial neuropathy with preferential degeneration of the popliteus muscle. Symptoms include pain, paresthesias, and decreased strength that originates in the knee and commonly extends to the plantar surface of the foot. These findings can be mistaken for lumbar neuropathies and compression of the sacral nerve roots. Differential diagnosis includes peripheral nerve sheath tumors, Baker’s cysts, extraneural ganglion cysts, and atypical vascular or lymphatic malformations. In this case report, the patient was a 61-year-old male, previously in good health, who presented with progressive pain in his medial left hamstring as well as weakness in left foot plantar flexion and paresthesias in the plantar aspect of his left foot. He first noticed impairments with his ability to push off with his left foot when running. His electromyogram (EMG) was abnormal and subsequent MRI of the left leg showed a complex intraneural ganglion cyst arising from the tibiofibular joint and ascending into the tibial nerve. He underwent indirect decompression through joint resection. Unfortunately, he did not have clinical improvement on one-year follow-up. Overall, symptomatic treatment of intraneural ganglion cyst includes decompression, surgical excision, or minimally invasive decompression by percutaneous aspiration of the ganglion under ultrasound guidance.

Giant Ganglion Cyst of the Proximal Tibiofibular Joint with Peroneal Nerve Palsy: A Case Report

Introduction:

Ganglion cysts are benign cystic tumors of musculoskeletal structures which have variable clinical presentations, however, compression neuropathies due to ganglion cyst are much less common in the lower extremity and only a couple of cases have been described in the literature. Hence, in the current case report, we describe a patient with a giant ganglion cyst causing peroneal nerve palsy which was managed surgically.

Case Report:

A 50-year-old female presented with a 2-month history of progressive left foot drop with a gradual development of swelling over the left fibular head. Imaging suggested ganglion cyst-induced peroneal nerve palsy. Initial conservative treatment failure warranted surgical excision which confirmed extraneural origin on histopathological examination. An immediate clinical improvement was observed postoperatively and full recovery occurred within 6 months. There was no recurrence at 2 years follow up

Conclusion:

The ganglion cyst-induced compression neuropathies are uncommon in lower limbs, especially in a skeletally mature person. Our case was an extraneural cyst which is the rare comparatively. The possibilities of other differentials should be excluded through imaging due to non-specific presentations. Surgical management is the preferred mode of treatment with 10% recurrences which can be reduced by complete excision including stalk.

Cystic degeneration of the tibial nerve: magnetic resonance neurography and sonography appearances of an intraneural ganglion cyst

Extra- and intraneural ganglion cysts have been described in the literature. The tibial nerve ganglion is uncommon and its occurrence without intra-articular extension is atypical. The pathogenesis of cystic degeneration localized to connective and perineural tissue secondary to chronic mechanical irritation or idiopathic mucoid degeneration is hypothesized. Since the above pathology is extremely rare and the magnetic resonance imaging examination detects the defining characteristics of the intrinsic alterations of the tibial nerve, the authors illustrate such a case of tibial intaneural ganglion cyst with its magnetic resonance neurography and sonography appearances.

Cystic lesions of peripheral nerves: Are we missing the diagnosis of the intraneural ganglion cyst?

AIM

To highlight the salient magnetic resonance imaging (MRI) features of the intraneural ganglion cyst (INGC) of various peripheral nerves for their precise diagnosis and to differentiate them from other intra and extra-neural cystic lesions.

METHODS

A retrospective analysis of the magnetic resonance (MR) images of a cohort of 245 patients presenting with nerve palsy involving different peripheral nerves was done. MR images were analyzed for the presence of a nerve lesion, and if found, it was further characterized as solid or cystic. The serial axial, coronal and sagittal MR images of the lesions diagnosed as INGC were studied for their pattern and the anatomical extent along the course of the affected nerve and its branches. Its relation to identifiable anatomical landmarks, intra-articular communication and presence of denervation changes in the muscles supplied by involved nerve was also studied.

RESULTS

A total of 45 cystic lesions in the intra or extraneural locations of the nerves were identified from the 245 MR scans done for patients presenting with nerve palsy. Out of these 45 cystic lesions, 13 were diagnosed to have INGC of a peripheral nerve on MRI. The other cystic lesions included extraneural ganglion cyst, paralabral cyst impinging upon the suprascapular nerve, cystic schwannoma and nerve abscesses related to Hansen's disease involving various peripheral nerves. Thirteen lesions of INGC were identified in 12 patients. Seven of these affected the common peroneal nerve with one patient having a bilateral involvement. Two lesions each were noted in the tibial and suprascapular nerves, and one each in the obturator and proximal sciatic nerve. An intra-articular connection along the articular branch was demonstrated in 12 out of 13 lesions. Varying stages of denervation atrophy of the supplied muscles of the affected nerves were seen in 7 cases. Out of these 13 lesions in 12 patients, 6 underwent surgery.

CONCLUSION

INGC is an important cause of reversible mono-neuropathy if diagnosed early and surgically treated. Its classic MRI pattern differentiates it from other lesions of the peripheral nerve and aid in its therapeutic planning. In each case, the joint connection has to be identified preoperatively, and the same should be excised during surgery to prevent further cyst recurrence.

Intraneural ganglion cyst involving the tibial nerve-a case report

Intraneural ganglia are rare non-neoplastic cysts that are caused by an accumulation of thick mucinous fluid. This occurs within the epineurium of peripheral nerves, which is encased in a dense fibrous capsule. The most common presentation of this tumour is local and/or radiating pain. Involvement of the tibial nerve is extremely uncommon, with less than 18 reported cases in the literature. We present a case of an intraneural tibial nerve ganglion cyst in a young male. We also discuss the current literature and proposed pathogenesis and treatment of this rare entity.

Tibial nerve intraneural ganglion cyst in a 10-year-old boy

Intraneural ganglion cysts are uncommon cystic lesions of peripheral nerves that are typically encountered in adults. In the lower extremity, the peroneal nerve is most frequently affected with involvement of the tibial nerve much less common. This article describes a tibial intraneural ganglion cyst in a 10-year-old boy. Although extremely rare, intraneural ganglion cysts of the tibial nerve should be considered when a nonenhancing cystic structure with intra-articular extension is identified along the course of the nerve. This report also details the unsuccessful attempt at percutaneous treatment with US-guided cyst aspiration and steroid injection, an option recently reported as a viable alternative to open surgical resection.

Ultrasound-guided aspiration and injection of an intraneural ganglion cyst of the common peroneal nerve

BACKGROUND

Intraneural ganglion cysts are rare, benign, mucinous lesions that occur within neural sheaths and are thought to involve cystic fluid exiting from nearby synovial joints. They often present as tender masses causing paresthesias in the distribution of the involved nerve, muscle weakness or cramping, or localized or referred pain.

CASE DESCRIPTION

We present a case of a patient who initially presented with foot drop due to an intraneural ganglion cyst of the common peroneal nerve. This cyst was successfully treated using ultrasound guidance to aspirate the cyst and inject corticosteroid to prevent further inflammation.

LITERATURE REVIEW

Standard of care has previously involved surgical resection, but this has been associated with a high frequency of recurrence. Due to the risks of nerve and vessel damage, there have been efforts to find alternative ways of resolving these cysts.

PURPOSES AND CLINICAL RELEVANCE

Aspiration and injection of corticosteroid is a useful and minimally invasive alternative to surgery for managing intraneural ganglion cysts.

A rare case of intraneural ganglion cyst involving the tibial nerve

Cystic lesions around the knee are a relatively common occurrence. Several types of cysts have been reported, including synovial, bursal, and ganglion. Ganglion cysts are not lined by synovial cells. Their location is highly variable, with occurrences described in the fat pads near the tibia or femur, muscles, nerves, and arteries. Intraneural ganglia are rare nonneoplastic cysts caused by the accumulation of thick mucinous fluid within the epineurium of peripheral nerves, encased in a dense fibrous capsule. These cysts can cause compression of the adjacent nerve fascicles, resulting in pain, paresthesias, weakness, muscle denervation, and atrophy. They are most commonly manifested by local and radiating pain, but sensory and motor deficits have also been described. Involvement of the tibial nerve is exceptionally rare, with <15 reported cases in the literature. We present a case of intraneural tibial ganglion cyst in a young woman. We also discuss the imaging features, differential considerations, proposed pathogenesis and anatomic origin, and treatment of this rare entity.

3T magnetic resonance neurography of tibial nerve pathologies

Diagnosis of tibial neuropathy has been traditionally based on clinical examination and electrodiagnostic studies; however, cross-sectional imaging modalities have been used to increase the diagnostic accuracy and provide anatomic mapping of the abnormalities. In this context, magnetic resonance neurography (MRN) offers high-resolution imaging of the tibial nerve (TN), its branches and the adjacent soft tissues, and provides an objective assessment of the neuromuscular anatomy, abnormality, and the surrounding pathology. This review describes the pathologies affecting the TN and illustrates their respective 3 Tesla (T) MRN appearances with relevant case examples.

Compression syndromes of the popliteal neurovascular bundle due to Baker cyst

BACKGROUND

The purpose of this study was to perform a comprehensive search of the literature for all studies, case reports, and series describing Baker cyst compression of the neurovascular bundle in the popliteal fossa and index their findings according to the structures compressed.

METHOD

Case reports and series obtained after a thorough MEDLINE search were indexed according to compressed structures. Patient demographics, main findings, method of diagnosis, cyst size, outcomes, and follow-up were recorded for each publication.

RESULTS

Signs and symptoms related to popliteal vein and tibial nerve compression were the most frequent presentation of symptomatic Baker cysts, due to the anatomic vulnerability of these structures within the popliteal fossa and their relative sensitivity to compression. Patients with tibial nerve entrapment demonstrated gastrocnemius muscle atrophy, paresthesias, and pain. Those with popliteal vein compression experienced swelling, pain, and rarely, venous thromboembolism. Isolated arterial compression, presenting with intermittent claudication, is a rare occurrence because it is a relatively stiff-walled vessel, has a higher pressure, and is located deep in the popliteal fossa. Combinations of these compression syndromes are most frequently encountered in the context of cyst rupture and resulting compartment syndrome.

CONCLUSIONS

Baker cyst is an important pathology for the differential diagnosis of popliteal neurovascular compression phenomena. It has a wide spectrum of presentation, therefore requiring accurate diagnosis for proper patient management. Because Baker cyst is by definition a chronic disorder, long-term follow-up is necessary to monitor patient recovery and prevent recurrence.

THE UNIFYING ARTICULAR (SYNOVIAL) ORIGIN OF INTRANEURAL GANGLIA

THE PATHOGENESIS OF intraneural ganglia has been an issue of curiosity, controversy, and contention for 200 years. Three major theories have been proposed to explain their existence, namely, 1) degenerative, 2) synovial (articular), and 3) tumoral theories, each of which only partially explains the observations made by a number of investigators. As a result, differing operative strategies have been described; these generally meet with incomplete neurological recoveries and high rates of recurrence. Recent advances in magnetic resonance imaging and critical analysis of the literature have clarified the mechanisms underlying the formation and propagation of these cysts, thereby confirming the unifying articular (synovial) theory. By identifying the shared features of the typical cases and explaining atypical examples or clinical outliers, several fundamental principles have been described. These include: 1) a joint origin; 2) dissection of fluid from that joint along an articular nerve branch, extension occurring via a path of least resistance; and 3) cyst size, extent, and directionality being influenced by pressures and pressure fluxes. We believe that understanding the pathogenesis of these cysts will be reflected in optimal surgical approaches, improved outcomes, and decreased frequency, if not elimination, of recurrences. This article describes the ongoing process of critically analyzing and challenging previous observations and evidence in an effort to prove a concept and a theory.

Magnetic resonance imaging of a deep peroneal intraneural ganglion cyst originating from the second metatarsophalangeal joint: a pattern of propagation supporting the unified articular (synovial) theory for the formation of intraneural ganglia

A deep peroneal intraneural cyst of the first web space of the foot is presented. Analysis of the magnetic resonance image scans revealed not only a connection with the medial aspect of the second metatarsophalangeal joint, but also the presence of an interconnected cyst within the lateral digital branch of the hallux. These characteristic magnetic resonance image findings are consistent with those previously described for a peroneal intraneural ganglion cyst that arose from the superior tibiofibular joint, and include (1) origin (ascent) from the second metatarsophalangeal joint with propagation along the articular branch and into the dorsal digital branch of the second toe, (2) cross-over within the shared epineurial sheath of the deep peroneal nerve, and (3) further propagation (descent) within the dorsal digital branch of the hallux. The analogous features between intraneural ganglion cysts affecting small and large-caliber nerves support the fundamental principles of the unified articular (synovial) theory for the formation of intraneural ganglia, including (1) a connection to a synovial joint, (2) dissection of joint fluid through a capsular rent along the articular branch into the parent nerve, and (3) intra-epineurial, pressure-dependent propagation of cyst fluid along paths of least resistance.

LEVEL OF CLINICAL EVIDENCE

4.

Hemorrhagic ganglion of the tibialis anterior tendon: report of an unusual variant

While clinicians have encountered heme-laden ganglion cysts in the past, to our knowledge the condition has never been described in the literature as a distinct pathological entity, namely, the hemorrhagic ganglion. Because hemorrhage may alter the appearance of an aspirate obtained from a ganglion cyst, and hemosiderin deposition within a ganglion cyst may alter the signal characteristics observed on a magnetic resonance image, such that both of these diagnostic methods may suggest the presence of a solid mass tumor rather than a ganglion cyst, it is important for clinicians and surgeons to be aware of the possibility of the presence of a hemorrhagic ganglion cyst. In this report, we present a case wherein a hemorrhagic ganglion cyst of the tibialis anterior tendon was identified and excised.

A posttraumatic, joint-connected sural intraneural ganglion cyst-with a new mechanism of intraneural recurrence: a case report

Intraneural ganglion cysts are rare in occurrence and most commonly involve the peroneal nerve at the fibular neck. We present a case of a traumatically induced intraneural ganglion cyst of the sural nerve that developed after a nondisplaced posterior malleolus ankle fracture. The intraneural ganglion cyst was connected to the subtalar joint by its articular branch and ascended several centimeters into the distal fourth of the leg. It was resected from the sural nerve proper and the posterior branch of the lateral calcaneal nerve, and the articular trunk was ligated. The patient developed subclinical intraneural recurrence, which was detected on a postoperative magnetic resonance imaging (MRI). Retrospective reinterpretation of the preoperative and postoperative MRIs revealed that ligation of the articular trunk proximal to a major branch (ie, the anterior branch of the lateral calcaneal nerve) led to increased intraneural cyst propagation distally: within the blind stump of the articular trunk and within several anterior branches of the lateral calcaneal nerve but not within the parent sural nerve or its continuation, the lateral dorsal cutaneous nerve. This mode of intraneural, but extraparental nerve recurrence can be easily understood by considering the altered fluid dynamics, particularly the increased resistance. This case report provides further evidence not only supporting the articular theory of intraneural ganglion formation but also highlighting the importance of searching for, identifying, and treating the pathologic articular branch connection near its joint connection in all cases.

LEVEL OF CLINICAL EVIDENCE

4.

The clinico-anatomic explanation for tibial intraneural ganglion cysts arising from the superior tibiofibular joint

OBJECTIVE

To demonstrate that tibial intraneural ganglia in the popliteal fossa are derived from the posterior portion of the superior tibiofibular joint, in a mechanism similar to that of peroneal intraneural ganglia, which have recently been shown to arise from the anterior portion of the same joint.

DESIGN

Retrospective clinical study and prospective anatomic study.

MATERIALS

The clinical records and MRI findings of three patients with tibial intraneural ganglion cysts were analyzed and compared with those of one patient with a tibial extraneural ganglion cyst and one volunteer. Seven cadaveric limbs were dissected to define the articular anatomy of the posterior aspect of the superior tibiofibular joint.

RESULTS

The condition of the three patients with intraneural ganglia recurred because their joint connections were not identified initially. In two patients there was no cyst recurrence when the joint connection was treated at revision surgery; the third patient did not wish to undergo additional surgery. The one patient with an extraneural ganglion had the joint connection identified at initial assessment and had successful surgery addressing the cyst and the joint connection. Retrospective evaluation of the tibial intraneural ganglion cysts revealed stereotypic features, which allowed their accurate diagnosis and distinction from extraneural cases. The intraneural cysts had tubular (rather than globular) appearances. They derived from the postero-inferior portion of the superior tibiofibular joint and followed the expected course of the articular branch on the posterior surface of the popliteus muscle. The cysts then extended intra-epineurially into the parent tibial nerves, where they contained displaced nerve fascicles. The extraneural cyst extrinsically compressed the tibial nerve but did not directly involve it. All cadaveric specimens demonstrated a small single articular branch, which derived from the tibial nerve to the popliteus. The branch coursed obliquely across the posterior surface of the popliteus muscle before innervating the postero-inferior aspect of the superior tibiofibular joint.

CONCLUSIONS

The clinical, MRI and anatomic features of tibial intraneural ganglion cysts are the posterior counterpart of the peroneal intraneural ganglion cysts arising from the anterior portion of the superior tibiofibular joint. These predictable features can be exploited and have implications for the pathogenesis of these intraneural cysts and treatment outcomes. These ganglion cysts are joint-related and provide further evidence to support the unifying articular theory. In each case the joint connection needs to be identified preoperatively, and the articular branches and the superior tibiofibular joint should be addressed operatively to prevent cyst recurrence.

Tibial intraneural ganglia in the tarsal tunnel: Is there a joint connection?

Intraneural ganglia are rare entities, and, as such, their pathogenesis has been extremely controversial. Recent evidence from intraneural ganglia occurring at more proximal sites-the peroneal nerve at the fibular neck (the most common site) and the tibial nerve at the knee-has suggested an articular origin rather than de novo formation. To our knowledge, of the 10 previous reports of tibial intraneural ganglia within the tarsal tunnel by others, a joint connection to the ankle joint was only identified in 2 cases. To support a hypothesis that tibial intraneural ganglia occurring within the tarsal tunnel region arise from neighboring joints, we analyzed 3 patients retrospectively, all of whom had magnetic resonance (MR) imaging and operative intervention. One of these patients was treated by a peripheral nerve surgeon specializing in foot and ankle surgery. The other 2 patients were the only ones previously published in the literature who had MR images available for reinterpretation. In none of these cases was a joint communication appreciated by radiologists interpreting the MR images preoperatively or by surgeons intraoperatively. Our review of these same cases demonstrated radiographic evidence of joint communications with the subtalar joints. Based on our findings in this article and our knowledge of intraneural ganglia occurring at more proximal sites, we believe that tibial intraneural ganglia within the tarsal tunnel originate from neighboring joints and that their connections to the joints (pedicles) are through articular branches. The importance of these connections is 2-fold: first, for their role in the pathogenesis of this entity, and second, for their potential therapeutic implications. As is highlighted by the clinical and radiographic follow-up in the 1 patient in this article and in many previously reported at other sites, intraneural cyst recurrence can occur if surgeons do not specifically address the articular connection.